The Aspirex catheter thrombectomy device (Straub Medical, Wangs, Switzerland) was specifically designed and developed for percutaneous interventional treatment of PE in pulmonary arteries, ranging from 6-14 mm in caliber. The central part of the catheter system is a high-speed rotational coil within the catheter body that: 1) creates negative pressure through an L-shaped aspiration port at the catheter tip, 2) macerates aspirated thrombus, and 3) removes macerated thrombus. The aspiration capacity of the Aspirex device was adjusted to remove thrombus from obstructed major pulmonary arteries and to minimize the risk of vascular collapse and vessel wall engagement. This was achieved by adjusting the caliber of the device, the pitch of the rotational coil, motor speed, and size or configuration of the aspiration port at the catheter tip.